Valve employed for the operation of pneumatic musical instruments



Jan. 14, 1930. BQREAU 1,743,876

VALVE EMPLOYED FOR THE OPERATION OF PNEUMATIC MUSICAL INSTRUMENTS I Filed Aug. 5, 192.7

Patented Jan. 14, 1930 V UNITED STATES PATENT OFFICE GABRIEL BOREAU, OF VERSAILLES, FRANCE Application filed August 5, 1927, Serial No. 210,956, and in France August 20, 1926.

In pneumatic musical instruments operated by means of valves by a perforated paper tune sheet, the head of a valve is mamtained raised, in such a way as to establish communication through this valve between the blower and the bellows or other pneumatic device to be actuated, only during the time when the perforation in the tracker bar, corresponding to this valve, is uncovered by a perforation in the paper band; as

- soon as the aperture is covered by the paper band, the head of the valve falls again and interrupts communication between the blower and bellows. If it is desired that the effect shall be maintained a relatively long time, it is necessary to give to the perforation a corresponding length which presents disadvantages from the point of View of the dimensions and the smooth travel of the band of perforated paper.

The present invention has for object a device allowing of obviating this disadvantage and which is particularly applicable in the case of apparatus for playing mechanically the violin or other stringed or bow instru ments, for example of the type described in the U. S. Letters Patent No. 1,608,658, issued on October 19, 1926, in which bellows, operated by the valves controlled by the perforated paper, have to produce the different movements of the bow and of the instrument, and must therefore remain actuated during a relatively long time.

According to the invention, the normal relay valve is provided with an auxiliary chamber connected to the valve chamber (or to its bellows, or to any other part where the reduced air pressure created by the functioning of this valve makes itself felt) a pipe system opening into the auxiliary chamber through a capillary or bleed hole, and the head of the valve is connected to a diaphragm closing this auxiliary chamber, in 45 such a way that when the valve is lifted, it is. kept lifted by reason of the reduced air pressure existing in the auxiliary chamber, until the moment when this auxiliary chamber is placed in communication with the atmosphere, for example by a pipe system connected to this chamber and likewise controlled by the perforated band.

The accompanying drawing represents by way of example a form of construction of the invention, in axial vertical section.

The valve is of the type usually employed in pneumatic musical instruments, that is to say that it comprises a chest or casing a, divided into two chambers a and a by a wall if; the latter forms a lower seating for the valve disc 6 while the upper seating a is formed by the upper wall of the box. This valve disc or head I) is connected by a stem 5 to a pilot resting upon a diaphragm constituting the upper wall of a small box 0, arranged at the lower part of the valve chest or casing a. The interior space 0 delimited byrv this box 0 communicates on the one hand with the tube or pipe system (Z extending to the main hole L, corresponding to the relay valve in question, of the tracker bar T.

On the other hand, the interior space 0 delimited by the box 0 communicates through a capillary hole 0 with the chamber a of the valve casing.

This chamber a is connected by the tub or pipe system c to the blower or suction chamber S, while the chamber a is connected by the tube or pipe system f to the bellows or other pneumatic device P to be actuated.

According to the invention, a pipe system 9 connects the chamber a to an auxiliary chamber it into which the pipe system 9 opens through a capillary hole 9 The auxiliary chamber h is closed at its lower part by a diaphragm k connected by a pilot 72, to the extended stem 6 of the valve disc 6. The auxiliary chamber h is, on the other hand, connected by a tube or pipe system i to an auxiliary hole 25 corresponding to the valve in question, in the tracker bar T, controlled by the band of perforated paper.

So long as the main hole t in the tracker bar T, connected to the tube d, is closed by the paper band, the valve disc 7) rests upon its lower seating, owing to the reduced air pressure existing in the chamber a connected to the blower or suction chamber S by the tube 6. In the interior of the box 0, at 0 there exists itself felt through the tube (Z upon the diaphragm c which is lifted, lifts in turn the valve disc I) and presses it against its upper seating 0*. Communication is thus established, passing through the chamber a between the blower or suction chamber S (by the tube 6) and the bellows P (by the tube f), which is actuated. The reduced air pressure existing in the chamber a likewise makes itself felt, through the pipe system 9 and the capillary hole 9 in the auxiliary chamber 72.; the diaphragm h of the latter lifts and ands its action, pulling upon the valve disc 5, to that of the diaphragm 0 which pushes back the valve disc Z) in the upward direction.

If then the main hole t in the tracker bar T, connected to the tube (Z, is covered by the paper band, the valve disc 6 does not fall, but is retained against its upper seating a owing to the reduced air pressure existing in the auxiliary chamber h. The parts remain in the ear e position until the auxiliary hole 6 in the tracker bar T, to which there extends the tube 2' connected to this chamber h, is uncovered by a perforation in the'paper band; at this moment the atmospheric pressure makes itself felt through this tube i'in 'b the chamber hand causes the diaphragm k to fall back, the capillary hole 9 preventing this pressure from making itself felt as rapidly through the pine system 9. The valve disc 6 therefore falls back. upon its lower seating a and the valve ceases to function.

It results from this arrangement that the valve commences to operate when the corresponding hole 6 in the tracker bar T is uncovered by a perforation; the actionof the valve does not cease, although this hole 25 be then masked by the paper band, until the corresponding auxiliary hole t in the tracker bar T is'uncove'red in its turn by another perforation.

Instead of being connected to the chamber a of the valve casing, between the two seat ings of the valve disc Z), the auxiliary cham her it might be connected to the bellows, or to any other part where the depression created by the operation of the valve makes itself felt.

This arrangement is evidently applicable to all mechanisms having pneumatic control by a perforated band, such as luminous advertisements.

sure admitted throu ha ertures in a tracker bar by perforations in a travelling paper band, apparatus for prolonging the stay of the valve in open position with respect to the pneumatics and the source of sub-pressure, beyond the time that the actuating perforation in the paper strip is in registry with the corresponding hole on the tracker bar, comprising auxiliary valve actuating means operated by sub-pressure to hold said valve open, and placed in communication with said source of sub-pressure by said valve when the latter is opened by the main valve actuating means, and means for relieving the sub-pressure which is in communication with said auxiliary means, for closing said valve, including a conduit communicating with said auxiliary means and with atmosphere, through an auxiliary hole in said tracker bar controlled by an appropriate hole in said paper band.

2. A relay valve device for the operation of pneumatic musical instruments comprising a suction chamber, a pneumatic operating chamber and a valve actuating chamber, av'alve controlling connection between said suction and pneumatic chambers and the communication of the pneumatic chamber with atmosphere, said valve actuating chamber communicating with said suction chamber by a bleed passage, a diaphragm forming a wall in said valve actuating chamber and operatively connected to said valve, a tracker ar, a pipe communicating with the valve actuating chamber and a main hole in the tracker bar adapted to be controlled by a perforated paper band and an auxiliary chamber having a diaphragm constituting a wall thereof and operatively connected to said valve said auxiliary chamber being connected to said pneumatic operating chamher by a bleed passage and a conduit communicating between said auxiliary chamher and an auxiliary hole in the tracker bar, also controlled by. said paper band, whereby said valve is suspended in position to maintain communication between said-suction chamber and pneumatic operating chamber during the interval from the opening of said main and said auxiliary holes in the tracker bar by appropriately positioned perforations on the paper strip.

3. A relay device for the operation of pneumatic musical instruments comprising a suction chamber, a pneumatic operating chamber and a valve actuating chamber, a valve controlling communication between said suction and pneumatic operating chambers, and the communication of the pneumatic operating chamber with atmosphere; said valve actuating chamber communicating with said suction chamber by a bleed passage,, a diaphragm forming a wall about said valve actuating chamber and operatively connected to said valve, a tracker bar, a pipe communicating with the valve actuating chamber and a main hole in the tracker bar adapted to be controlled by a perforated paper band, and an auxiliary chamber having a diaphragm constituting a wall thereof and operatively connected to said valve, said auxiliary chamber being connected to a region of sub-pressure created by the opening of said valve, by a bleed passage, and a conduit communicating between said auxiliary chamber and an auxiliary hole of the tracker bar also controlled by the perforated paper band, whereby said valve is suspended in position to maintain communication between said suction chamber and the pneumatic operating chamber during the interval from the opening of said main and auxiliary holes in the tracker bar, by appropriately positioned perforations on the paper strip.

In testimony whereof I have signed my name to this specification.

GABRIEL BOREAU. 

